.header {
  height: 60px;
  background: #253545;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
  display: flex;
  justify-content: flex-end;
  align-items: center;
  padding: 0 20px;
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
}

.logout-btn {
  background: none;
  border: none;
  color: #3a7bd5;
  font-size: 14px;
  cursor: pointer;
}
.main {
  display: flex;
  margin-top: 60px;
  min-height: calc(100vh - 60px);
}

.sidebar {
  width: 220px;
  background: #2c3e50;
  color: white;
  padding: 20px 0;
  position: fixed;
  height: calc(100vh - 60px);
  overflow-y: auto;
}

.logo img {
  width: 60px;
  display: block;
  margin: 0 auto 15px;
}

.system-title {
  text-align: center;
  font-size: 18px;
  margin-bottom: 30px;
  font-weight: bold;
}

/* ========== 菜单样式 ========== */
.menu {
  list-style: none;
  padding: 0 20px;
  margin: 0;
}

.menu li {
  margin-bottom: 10px;
}

.menu-link,
.menu-item {
  display: flex;
  justify-content: space-between;
  align-items: center;
  color: #ecf0f1;
  text-decoration: none;
  padding: 10px;
  border-radius: 4px;
  cursor: pointer;
}

.menu-link:hover,
.menu-item:hover {
  background: #34495e;
}

.toggle-icon {
  font-size: 12px;
}

.submenu {
  list-style: none;
  padding-left: 20px;
  margin: 8px 0 0;
}

.submenu li {
  margin: 4px 0;
}

.submenu a {
  color: #ecf0f1;
  text-decoration: none;
  display: block;
  padding: 8px 10px;
  border-radius: 4px;
}

.submenu a:hover {
  background: #34495e;
}
